Use these steps: Get two pickaxes alike, e.g. two diamond pickaxes. Preferably with same enchantments. My diamond pickaxes both had Fortune III, Unbreaking III and Efficiency IV. Start mining using just one of them. When the first is used up and it breaks it usually also drops itself (and you CAN pick it up again and use it to mine for a few seconds more, though in this case I could not locate where it had droped). This is the point when I look for my other new pickaxe in my inventory. But I could not find that one either. Later though it turns up. This is the best I can guide you in retracing my steps.
NOTE 3: The new Pickaxe has appeared again! I don't know how. I was close to the place where it vanished. But believe me, there was no sign of it anywhere when I first looked for it. Could it be hiding, somehow inside the walls?
Thomas Tveding
Use these steps:
Get two pickaxes alike, e.g. two diamond pickaxes. Preferably with same enchantments. My diamond pickaxes both had Fortune III, Unbreaking III and Efficiency IV. Start mining using just one of them. When the first is used up and it breaks it usually also drops itself (and you CAN pick it up again and use it to mine for a few seconds more, though in this case I could not locate where it had droped). This is the point when I look for my other new pickaxe in my inventory. But I could not find that one either. Later though it turns up.
This is the best I can guide you in retracing my steps.